WO2023056838A1 - Thin film and preparation method therefor, photoelectric device - Google Patents

Abstract

The present application discloses a thin film and a preparation method therefor, a photoelectric device, and a display device. The thin film comprise a metal oxide nanomaterial doped with a triazine framework material. When the thin film is used as a hole transport layer, the triazine framework material enables better matching of the energy level of the hole transport layer and a light-emitting layer, thereby facilitating the balance of electron-hole injection, improving the conductivity of metal oxide nanoparticles, and increasing the hole transport rate, thus synergistically improving the luminous efficiency of the photoelectric device.

Description

Thin film and its preparation method, optoelectronic device

This application claims the priority of the Chinese patent application with the application number 202111171832.6 and the application title "a hole transport thin film and its preparation method, optoelectronic device and display device" filed at the China Patent Office on October 08, 2021 , the entire contents of which are incorporated in this application by reference.

technical field

The present application relates to the field of display technology, in particular to a thin film, a preparation method thereof, and a photoelectric device.

Background technique

Optoelectronic devices refer to devices made according to the photoelectric effect, which have a wide range of applications in new energy, sensing, communication, display, lighting and other fields, such as solar cells, photodetectors, organic electroluminescent devices (OLED) or quantum dots Electroluminescent devices (QLEDs). The structure of a traditional optoelectronic device mainly includes an anode, a hole injection layer, a hole transport layer (ie, a hole transport film), a light emitting layer, an electron transport layer, an electron injection layer and a cathode. Under the action of the electric field, the holes generated by the anode of the photoelectric device and the electrons generated by the cathode move, inject into the hole transport layer and the electron transport layer respectively, and finally migrate to the light-emitting layer. When the two meet in the light-emitting layer, a Energy excitons, which excite light-emitting molecules and eventually produce visible light.

The traditional organic hole transport material PEDOT:PSS is widely used in optoelectronic devices, such as OPV, OFET, perovskite solar cells, OLED, QLED and other fields, and has achieved good results. However, the PEDOT:PSS material is acidic on the one hand and is easy to corrode the surface of the ITO conductive glass. On the other hand, it is hygroscopic and is easily eroded by water vapor in the air, so it has an adverse effect on the stability of the device. Compared with organic hole transport materials, inorganic hole transport materials have superior stability, higher hole mobility, and low cost, and can be solution processed.

technical problem

However, the hole transport layer prepared by the existing metal oxide nanomaterials has problems such as poor energy level matching with the light-emitting layer and poor conductivity, which leads to low efficiency of optoelectronic devices.

technical solution

Therefore, the present application provides a thin film, a preparation method thereof, and an optoelectronic device.

An embodiment of the present application provides a thin film, which includes a metal oxide nanomaterial doped with a triazine framework material.

Optionally, in some embodiments of the present application, the thin film is composed of a metal oxide nanomaterial doped with a triazine framework material.

Optionally, in some embodiments of the present application, the triazine skeleton material is polymerized from monomers, and the monomers are nitrile compounds containing aromatic groups.

Optionally, in some embodiments of the present application, the aromatic group-containing nitrile compound is selected from cyano-substituted benzene ring compounds, cyano-substituted pyridine compounds, cyano-substituted pyrimidine compounds, cyano-substituted biphenyl One or more of compounds, cyano-substituted naphthalene ring compounds.

Optionally, in some embodiments of the present application, the aromatic group-containing nitrile compound includes at least two cyano groups, and the aromatic group-containing nitrile compound is selected from tricyanobenzene, p-cyanobenzene, biphenyl One or more of dinitrile and pyridinedicarbonitrile.

Optionally, in some embodiments of the present application, in the metal oxide nanomaterial doped with a triazine framework material, the molar ratio of the metal oxide to the triazine framework material ranges from 1:(1- 1.5).

Optionally, in some embodiments of the present application, the metal oxide nanomaterial is selected from one or more of nickel oxide, molybdenum oxide, tungsten oxide, copper oxide, vanadium oxide and chromium oxide Various.

Optionally, in some embodiments of the present application, the degree of polymerization of the triazine framework material is 900-3000.

Correspondingly, the embodiment of the present application also provides a method for preparing a thin film, including the following steps: preparing a metal oxide precursor doped with a triazine framework material; providing a substrate, and dissolving the metal oxide precursor doped with a triazine framework material The precursor is arranged on the substrate to obtain a thin film of metal oxide nanomaterials doped with triazine framework materials.

Optionally, in some embodiments of the present application, the step of preparing a metal oxide precursor doped with a triazine framework material includes: providing a metal salt, a triazine framework material and a solvent, and mixing them to obtain a doped triazine framework material. A metal salt mixture solution of an azine skeleton material; adding an alkali into the metal salt mixture solution to obtain a metal oxide precursor doped with a triazine skeleton material.

Optionally, in some embodiments of the present application, the metal salt is selected from one or more of metal chloride salts, metal nitrates, and metal acetylacetonate salts.

Optionally, in some embodiments of the present application, the base is selected from one or more of sodium hydroxide, potassium hydroxide and tetramethylammonium hydroxide.

Optionally, in some embodiments of the present application, the solvent is selected from one or more of methanol, ethanol, ethylene glycol, glycerol, butanol, DMF, and DMSO.

Optionally, in some embodiments of the present application, the substrate is provided, and the metal oxide precursor doped with a triazine framework material is placed on the substrate to obtain a metal oxide precursor comprising a doped triazine framework material. The step of the thin film of nanomaterials includes: providing a substrate, and setting the metal oxide precursor of the doped triazine framework material on the substrate by a solution method; drying treatment to obtain the doped triazine framework material thin films of metal oxide nanomaterials.

Correspondingly, the embodiment of the present application also provides a photoelectric device, comprising a stacked anode, a hole transport layer, a light-emitting layer and a cathode, the hole transport layer is the above thin film, or the hole transport layer consists of Prepared by the above film preparation method.

Optionally, in some embodiments of the present application, the light-emitting layer is an organic light-emitting layer or a quantum dot light-emitting layer, and the material of the organic light-emitting layer is selected from diarylanthracene derivatives, distyryl aromatic derivatives One or more of pyrene derivatives or fluorene derivatives, blue-emitting TBPe fluorescent materials, green-emitting TTPA fluorescent materials, orange-emitting TBRb fluorescent materials, and red-emitting DBP fluorescent materials; The material of the quantum dot light-emitting layer is selected from at least one of single-structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials, and the single-structure quantum dots are selected from II-VI group compounds and IV-VI group compounds , III-V compound and at least one of I-III-VI compound, the II-VI compound is selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS 、CdSeTe、CdSTe、ZnSeS、ZnSeTe、ZnSTe、HgSeS、HgSeTe、HgSTe、CdZnS、CdZnSe、CdZnTe、CdHgS、CdHgSe、CdHgTe、HgZnS、HgZnSe、HgZnTe、CdZnSeS、CdZnSeTe、CdZnSTe、CdHgSeS、CdHgSeTe、CdHgSTe、HgZnSeS、HgZnSeTe And at least one of HgZnSTe, the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe , SnPbSTe at least one, the III-V compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb , AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb At least one of them, the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2; the core of the quantum dot with the core-shell structure is selected from any of the above-mentioned single-structure quantum dots , the shell material of the quantum dots with core-shell structure is selected from at least one of CdS, CdTe, CdSeTe, CdZnSe, CdZnS, CdSeS, ZnSe, ZnSeS and ZnS.

Optionally, in some embodiments of the present application, the anode and the cathode are each independently selected from one or more of metal electrodes, carbon material electrodes, metal oxide electrodes and composite electrodes, and the metal electrodes One or more selected from Al, Ag, Cu, Mo, Au, Ba, Ca and Mg, and the carbon material electrode is selected from one or more of graphite, carbon nanotubes, graphene and carbon fibers; The metal oxide electrode is selected from one or more of doped or non-doped ITO, FTO, ATO, AZO, GZO, IZO, MZO and AMO, and the composite electrode is selected from AZO/Ag/AZO, AZO /Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS , ZnS/Al/ZnS, TiO ₂ /Ag/TiO ₂ and one or more of TiO ₂ /Al/TiO ₂ .

Optionally, in some embodiments of the present application, the optoelectronic device may further include an electron transport layer, and the electron transport layer is located between the light emitting layer and the cathode.

Optionally, in some embodiments of the present application, the material of the electron transport layer can be selected from one or more of inorganic nanocrystalline materials, doped inorganic nanocrystalline materials, and organic materials, and the inorganic nanocrystalline The material is selected from one or more of zinc oxide, titanium dioxide, tin dioxide, aluminum oxide, calcium oxide, silicon dioxide, gallium oxide, and zirconia, and the doped inorganic nanocrystalline material includes zinc oxide dopant, One or more of titanium dioxide dopant, tin dioxide dopant, wherein, the doping element contained in the doped inorganic nanocrystalline material is selected from Mg, Ca, Li, Ga, Al, Co, Mn , the organic material is selected from one or both of polymethyl methacrylate and polyvinyl butyral.

Optionally, in some embodiments of the present application, the hole transport layer has a thickness of 10 to 60 nm.

Beneficial effect

The thin films of the present application include metal oxide nanomaterials doped with triazine framework materials. Among them, the triazine framework material has good chemical stability and thermal stability, and is a porous material. The triazine framework material is rich in nitrogen, and the surface is polar, which can induce the formation of Strong molecular dipole, so as to adjust the energy level position, so that the energy level of the hole transport layer and the light-emitting layer can be more matched, which is beneficial to the injection and transport of holes, and promotes the electron-hole balance. At the same time, the covalent triazine ring skeleton has a layered structure and a high specific surface area, which has a coating effect on the metal oxide nanoparticles. The two are in close contact, which can effectively control the nucleation rate of the metal oxide nanoparticles and passivate them. Its surface defects reduce the surface energy of the polar surface and increase the crystallinity of the material, thereby improving the conductivity of the metal oxide nanoparticles, increasing the hole transport rate, and synergistically improving device performance and device efficiency.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is a schematic structural diagram of an optoelectronic device provided by an embodiment of the present application;

Fig. 2 is a schematic flow chart of a method for preparing a hole transport thin film provided in an embodiment of the present application;

Fig. 3 is a schematic flow chart of a specific embodiment of step S10 in Fig. 2;

Fig. 4 is a schematic flow chart of a specific embodiment of step S20 in Fig. 2;

Fig. 5 is a schematic flow chart of a method for preparing an optoelectronic device provided in an embodiment of the present application;

Fig. 6 is a schematic flow chart of another method for preparing an optoelectronic device provided in the embodiment of the present application;

Fig. 7 is a schematic structural view of the triazine framework materials CTF-1 and CTF-2 provided by the present application. .

Embodiment of this application

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of this application.

Embodiments of the present application provide a hole transport thin film, a preparation method thereof, and a photoelectric device. Each will be described in detail below. It should be noted that the description sequence of the following embodiments is not intended to limit the preferred sequence of the embodiments. In addition, in the description of the present application, the term "including" means "including but not limited to". Various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the application; therefore, the described range should be regarded as The description has specifically disclosed all possible subranges as well as individual values within that range. For example, a description of a range from 1 to 6 should be considered to have specifically disclosed subranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and Single numbers within the stated ranges, eg 1, 2, 3, 4, 5 and 6, apply regardless of the range. Additionally, whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range.

In this application, "and/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which may mean: A exists alone, A and B exist simultaneously, and B exists alone Condition. Among them, A and B can be singular or plural.

In this application, "one or more" means one or more, and "multiple" means two or more. "One or more", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one item (unit) of a, b, or c", or "at least one item (unit) of a, b, and c" can mean: a, b, c, a-b( That is, a and b), a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

Please refer to FIG. 1 , the embodiment of the present application provides a hole transport thin film 10 , which is mainly used in a photoelectric device 100 . The hole transport film 10 includes a metal oxide nanomaterial doped with a triazine framework material, and the metal oxide nanomaterial doped with a triazine framework material can be abbreviated as MOx/CTF, wherein MOx is a metal oxide and CTF is a triazine Skeleton material.

In this embodiment, in the metal oxide nanomaterial doped with triazine framework material, since the triazine framework material contains abundant nitrogen elements, the surface has polarity, which can induce the formation of strong molecules on the interface of the metal oxide nanomaterial layer. Dipole, so as to adjust the energy level position, so that the metal oxide nanomaterial hole transport film 10 and the energy level of the light-emitting layer are more matched, which is beneficial to the electron-hole injection balance of the photoelectric device 100 including the hole transport film 10 . At the same time, the covalent triazine ring skeleton is a layered porous structure with a large specific surface area, which can have a coating effect on metal oxide nanoparticles. The two are in close contact, which can effectively control the nucleation rate of metal oxide nanoparticles. Passivate its surface defects, reduce the surface energy of the polar surface, and increase the crystallinity of the material, thereby improving the conductivity of the metal oxide nanoparticles and increasing the hole transport rate. The above two synergistically improve the luminous efficiency of the optoelectronic device 100 and reduce the turn-on voltage of the optoelectronic device 100 . In addition, the triazine framework material itself has good chemical stability and thermal stability, and doping in metal oxide nanomaterials as a hole transport material will not affect the chemical stability and stability of the hole transport film 10 and the photoelectric device 100. Thermal stability is negatively affected.

In this embodiment, the hole transport thin film 10 may consist only of metal oxide nanomaterials doped with a triazine framework material, and may also include other materials other than the metal oxide nanomaterials doped with a triazine framework material. For example, conventional organic hole transport materials such as PEDOT:PSS, or metal particles may also be included.

In this embodiment, the triazine skeleton material is polymerized from monomers, and the monomers are nitrile compounds containing aromatic groups. Among them, the nitrile compounds containing aromatic groups may also be called aromatic nitrile compounds, cyano-substituted aromatic compounds or cyano-substituted aromatic ring compounds. Specifically, the cyano group in the aromatic group-containing nitrile compound undergoes cyclotrimerization under certain conditions to form a triazine ring structure, and multiple triazine ring structures form a triazine skeleton material. It can be understood that the triazine skeleton material in the present application can also be obtained in other ways, and the triazine skeleton material in the present application is not limited to being polymerized by aromatic group-containing nitrile compounds, and also includes other methods known in the art The prepared triazine skeleton material.

In some embodiments of the present application, the aromatic group-containing nitrile compound as a monomer can be selected from cyano-substituted benzene ring compounds, cyano-substituted pyridine compounds, cyano-substituted pyrimidine compounds, cyano-substituted biphenyls Compounds, cyano-substituted naphthalene ring compounds. That is, the aromatic group in the aromatic group-containing nitrile compound can be a benzene ring, a pyridine ring, a pyrimidine ring, a biphenyl ring, or a naphthalene ring.

In some embodiments of the present application, the aromatic group-containing nitrile compound includes at least two cyano groups. Two or more cyano groups can increase the reaction sites of the monomers to perform cyclotrimerization into a triazine ring structure. Each cyano group can participate in the formation of a triazine ring structure, then at least two cyano groups can support each monomer to participate in the formation of at least two triazine ring structures, and can link multiple triazine ring structures to form polymerization High-strength triazine skeleton material. Specifically, the aromatic group-containing nitrile compound may be p-cyanobenzene, biphenyl dicyanonitrile or pyridinedicarbonitrile containing two cyano groups, or tricyanobenzene containing three cyano groups. Wherein, tricyanobenzene may be 1,3,5-tricyano-substituted phenyl or 1,3,5-benzenetricyano.

It can be understood that a triazine skeleton material in this embodiment can be polymerized from one monomer, or can be polymerized from two or more different monomers. For example, the triazine skeleton material can be polymerized from two monomers, p-cyanobenzene and tricyanobenzene.

It can be understood that the metal oxide nanomaterial in this embodiment may be doped with one triazine framework material, or may be doped with two or more than two kinds of triazine framework materials. For example, the metal oxide nanomaterial can be doped with a triazine skeleton material formed by the polymerization of p-cyanobenzene, and also doped with a triazine skeleton material formed by the polymerization of tricyanobenzene.

In some embodiments of the present application, in the metal oxide nanomaterial doped with the triazine framework material, the molar ratio of the metal oxide to the triazine framework material ranges from 1:(1-1.5). Specifically, the molar ratio of the metal oxide to the triazine framework material may be 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5. If the content of the triazine framework material is too low, it is difficult to achieve the effect of increasing the hole transport rate of the hole transport film 10; if the content of the triazine framework material is too high, the charge transport performance of the hole transport film 10 will be reduced. The triazine skeleton material is a polymer, and the molar ratio can be calculated from its average molecular weight. Among them, the average molecular weight can be obtained by the product of the average polymerization degree and the monomer molecular weight, and the average polymerization degree can be obtained by viscosity test. In this embodiment, the degree of polymerization of the triazine framework material can be controlled at 900-3000.

In some embodiments of the present application, metal oxide nanomaterials can be selected from inorganic materials with hole transport capabilities, such as doped or non-doped nickel oxides, molybdenum oxides, tungsten oxides, copper oxides, etc. One or more of oxides, vanadium oxides and chromium oxides. That is, the metal oxide nanomaterial can be selected from one or more of doped or non-doped NiOx, MoOx, WOx, CuOx, VOx, and CrOx, wherein x is set according to the valence of each element in the compound. Specifically, the metal oxide nanomaterial may be selected from one or more of NiO, MoO ₃ , WO ₃ , CuO, V ₂ O ₅ and CrO ₃ .

The embodiment of the present application also provides a method for preparing a hole transport film 10, please refer to FIG. 2. FIG. 2 is a flowchart of a method for preparing a hole transport film provided in an embodiment of the present application, including the following steps:

Step S10: preparing a metal oxide precursor doped with a triazine framework material.

In this embodiment, the triazine skeleton material is polymerized from monomers, and the monomers are nitrile compounds containing aromatic groups. Among them, the nitrile compounds containing aromatic groups may also be called aromatic nitrile compounds, cyano-substituted aromatic compounds or cyano-substituted aromatic ring compounds. Specifically, the cyano group in the aromatic group-containing nitrile compound undergoes cyclotrimerization under certain conditions to form a triazine ring structure, and multiple triazine ring structures form a triazine skeleton material.

In some embodiments of the present application, the aromatic group-containing nitrile compound as a monomer can be selected from cyano-substituted benzene ring compounds, cyano-substituted pyridine compounds, cyano-substituted pyrimidine compounds, cyano-substituted biphenyls Compounds, cyano-substituted naphthalene ring compounds. That is, the aromatic group in the aromatic group-containing nitrile compound can be a benzene ring, a pyridine ring, a pyrimidine ring, a biphenyl ring, or a naphthalene ring.

In some embodiments of the present application, the aromatic group-containing nitrile compound includes at least two cyano groups. Two and more than two cyano groups can increase the reaction sites of monomers to carry out cyclotrimerization into triazine ring structure. Each cyano group can participate in the formation of a triazine ring structure, then at least two cyano groups can support each monomer to participate in the formation of at least two triazine ring structures, and can link multiple triazine ring structures to form polymerization High-strength triazine skeleton material. Specifically, the aromatic group-containing nitrile compound may be p-cyanobenzene, biphenyl dicyanonitrile or pyridinedicarbonitrile containing two cyano groups, or tricyanobenzene containing three cyano groups. Wherein, tricyanobenzene may be 1,3,5-tricyano-substituted phenyl or 1,3,5-benzenetricyano.

It can be understood that a triazine skeleton material in this embodiment can be polymerized from one monomer, or can be polymerized from two or more different monomers. For example, the triazine skeleton material can be polymerized from two monomers, p-cyanobenzene and tricyanobenzene.

It can be understood that the metal oxide nanomaterial in this embodiment may be doped with one triazine framework material, or may be doped with two or more than two kinds of triazine framework materials. For example, the metal oxide nanomaterial can be doped with a triazine skeleton material formed by the polymerization of p-cyanobenzene, and also doped with a triazine skeleton material formed by the polymerization of tricyanobenzene.

In one embodiment, referring to FIG. 3, FIG. 3 is a schematic flowchart of a specific embodiment of step S10 in FIG. 2, and step S10 may specifically include:

Step S11: providing a metal salt, a triazine framework material, and a solvent, and mixing them to obtain a metal salt mixture solution doped with a triazine framework material.

In this step, the metal salt may be selected from one or more of metal chloride salts, metal nitrates, and metal acetylacetonate salts. Taking metallic nickel as an example, the nickel salt may be nickel chloride, nickel nitrate or nickel acetylacetonate.

In this step, the solvent used may be selected from one or more of alcohol, DMF and DMSO. Wherein, the alcohol can be fatty alcohols such as methanol, ethanol, ethylene glycol, propanol, glycerol, butanol. Using alcohol as a solvent can avoid the formation of non-bridging hydroxyl groups on the surface of the metal oxide nanomaterials, thereby reducing the occurrence of agglomeration. Moreover, due to the physical and chemical adsorption of alcohol in the precursor particles, it can further prevent the particles from approaching, and can effectively reduce the formation of agglomerates. In order to uniformly mix the triazine framework material and the metal salt in the metal salt mixture solution doped with the triazine framework material, stirring and mixing or ultrasonic treatment can be performed to fully disperse and mix.

It can be understood that one or more mentioned in this application includes one, two and more than two.

Step S12: adding a base into the metal salt mixture solution to obtain a metal oxide precursor doped with a triazine framework material.

Wherein, the base can be selected from one or more of sodium hydroxide, potassium hydroxide and tetramethylammonium hydroxide.

In this step, a base is added to the metal salt mixture solution to obtain a metal oxide precursor doped with a triazine framework material with a pH value in the range of 8-14. That is, the pH range of metal oxide precursors doped with triazine framework materials is 8-14, and the alkaline environment is conducive to the formation of subsequent metal oxide nanomaterials, and the pH value of metal oxide precursors is too low, which will lead to metal oxidation. The surface of the material nanomaterials is easier to form more hydroxyl ligands, which leads to agglomeration; while the pH value of the metal oxide precursor is too high, the particle size of the formed metal oxide nanomaterials is too small, and has more of surface defects.

In order to reduce the occurrence of phenomena such as uneven size and agglomeration of nanoparticles, the base can be slowly added to the metal salt mixture solution, for example, in a slow dropwise manner. Wherein, the base can be dissolved in alcohol to form an alcoholic solution of the base, and the alcohol can be used as a solvent on the one hand, and a diluent for the base on the other hand, thereby reducing the subsequent agglomeration of metal oxide nanoparticles.

After adding the alkali to adjust the pH value of the solution, it can be stirred for a certain period of time, such as 1-6 hours, so that the solution of the metal oxide precursor doped with the triazine framework material is mixed evenly, and the triazine framework material and the metal oxide precursor Sufficient contact, so as to reduce the particle agglomeration phenomenon during the subsequent generation of metal oxide nanoparticles, and make the triazine skeleton material wrap the metal oxide nanoparticles, effectively control the nucleation rate of the metal oxide nanoparticles, and passivate its surface defects.

After the metal oxide precursor doped with the triazine framework material is prepared in the above steps, step S20 is performed.

Step S20: providing a substrate, and disposing a metal oxide precursor doped with a triazine framework material on the substrate to obtain a hole transport thin film comprising a metal oxide nanomaterial doped with a triazine framework material.

In some embodiments of the present application, metal oxide nanomaterials can be selected from inorganic materials with hole transport capabilities, such as doped or non-doped nickel oxides, molybdenum oxides, tungsten oxides, and copper oxides. One or more of compounds, vanadium oxides and chromium oxides. That is, the metal oxide nanomaterial can be selected from one or more of doped or non-doped NiOx, MoOx, WOx, CuOx, VOx, and CrOx, wherein x is set according to the valence of each element in the compound. Specifically, the metal oxide nanomaterial may be selected from one or more of NiO, MoO ₃ , WO ₃ , CuO, V ₂ O ₅ and CrO ₃ . In order to prepare a certain metal oxide nanomaterial, in step S10, a metal salt of the corresponding metal needs to be used. For example, if nickel salt is used in step S10 , then in this step, a hole transport thin film 10 comprising nickel oxide nanomaterial doped with a triazine framework material is obtained.

In some embodiments of the present application, in the hole transport film prepared in this step, the molar ratio of the metal oxide to the triazine framework material is in the range of 1:(1-1.5). Specifically, the molar ratio of the metal oxide to the triazine framework material may be 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5. Correspondingly, in order to make the hole-transport film of the metal oxide nanomaterial doped with the triazine framework material obtained in step S20, the range of the molar ratio of the metal oxide to the triazine framework material is 1:(1-1.5) In the last step S10, the molar ratio of the metal oxide precursor and the triazine framework material can be controlled within a preset range, or the metal salt and the triazine framework material can be added according to a preset ratio in step S11.

Specifically, referring to FIG. 4, FIG. 4 is a schematic flow chart of a specific embodiment of step S20 in FIG. 2, and step S20 may specifically include:

Step S21: providing a substrate, and disposing a metal oxide precursor doped with a triazine framework material on the substrate by a solution method.

In this step, the metal oxide precursor doped with the triazine framework material is in a solution state, and when it is placed on the substrate, a wet film or solution layer is formed on the substrate. Among them, the solution method includes but not limited to spin coating, coating, inkjet printing, blade coating, immersion pulling, soaking, spray coating, roll coating or casting. In this step, the thickness of the hole transport film 10 finally formed can be controlled and adjusted by controlling and adjusting the solution concentration and other conditions used in the solution method. Wherein, the thickness range of the hole transport film 10 may be 10 to 60 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm and so on. Taking spin coating as an example, the thickness can be controlled by adjusting the concentration of the solution, the spin coating speed and the spin coating time. For example, the spin coating speed can be 2000-6000rpm/min, and the spin coating time can be 30-90s.

Step S22: drying treatment to obtain a hole transport thin film comprising a metal oxide nanomaterial doped with a triazine framework material.

In the previous step S21, after the wet film or solution layer is formed on the substrate, it is dried in this step to remove the solvent to obtain a dry hole transport film.

The drying treatment in this step may be an annealing treatment. Among them, "annealing process" includes all treatment processes that can make the wet film obtain higher energy, thereby changing from a wet film state to a dry state. Hold for a specific time to fully volatilize the solvent in the wet film; for another example, the "annealing process" can also include a sequential heat treatment process and cooling process, that is, the wet film is heated to a specific temperature, and then kept for a specific time to make the first wet film The solvent in the film is fully volatilized, and then cooled at an appropriate speed to eliminate residual stress and reduce the risk of layer deformation and cracks in the dry hole transport film.

It can be understood that the type of the substrate is not limited. In one embodiment, the substrate is an anode substrate, and the hole transport thin film 10 comprising a metal oxide nanomaterial doped with a triazine framework material is disposed on the anode 20 . The substrate may be a commonly used substrate, for example, a rigid substrate made of glass; or a flexible substrate made of polyimide. The material of the anode 20 can be, for example, one or more of metal, carbon material and metal oxide, and the metal can be, for example, one or more of Al, Ag, Cu, Mo, Au, Ba, Ca and Mg; Carbon materials can be one or more of graphite, carbon nanotubes, graphene and carbon fibers; metal oxides can be doped or non-doped metal oxides, including ITO, FTO, ATO, AZO, GZO, IZO One or more of , MZO and AMO, also including composite electrodes sandwiching metal between doped or non-doped transparent metal oxides, composite electrodes include but not limited to AZO/Ag/AZO, AZO/Al/ AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS, ZnS/ One or more of Al/ZnS, TiO ₂ /Ag/TiO ₂ and TiO ₂ /Al/TiO ₂ . Wherein, "/" represents a laminated structure, for example, the composite electrode AZO/Ag/AZO represents an electrode of a composite structure composed of three layers of AZO layer, Ag layer and AZO layer. In another embodiment, the substrate includes a cathode, an electron transport film and a light-emitting layer stacked, and the hole transport film 10 comprising a metal oxide nanomaterial doped with a triazine framework material is disposed on the light-emitting layer.

Please refer to FIG. 1 , the embodiment of the present application also provides an optoelectronic device 100, which may be a solar cell, a photodetector, an organic electroluminescent device (OLED) or a quantum dot electroluminescent device (QLED). The photoelectric device 100 includes an anode 20 , a hole transport layer, a light emitting layer 30 and a cathode 40 stacked in sequence.

The material of the anode 20 is a material known in the art for an anode, and the material of the cathode 40 is a material known in the art for a cathode. The anode 20 and the cathode 40 are selected from one or more of metal electrodes, carbon material electrodes, metal oxide electrodes and composite electrodes, and the metal electrodes can be, for example, Al, Ag, Cu, Mo, Au, Ba, Ca and One or more of Mg; carbon material electrodes can be one or more of graphite, carbon nanotubes, graphene and carbon fibers, for example; metal oxide electrodes can be doped or non-doped metal oxides, including One or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO and AMO, the composite electrode includes but not limited to AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS, ZnS/Al/ZnS, TiO ₂ /Ag One or more of TiO 2 /TiO ₂ and TiO ₂ /Al/TiO ₂ . Wherein, "/" represents a laminated structure, for example, the composite electrode AZO/Ag/AZO represents an electrode of a composite structure composed of three layers of AZO layer, Ag layer and AZO layer.

The thickness of the anode 20 can be, for example, 10nm to 200nm, such as 40nm, 60nm, 80nm, etc.; the thickness of the cathode 40 can be, for example, 10nm to 200nm, such as 40nm, 60nm, 80nm, etc.

The hole transport layer is the hole transport film 10 mentioned above, which can be referred to the relevant description above, and will not be repeated here. The thickness of the hole transport film 10 may range from 10 to 60nm, such as 10nm, 20nm, 30nm, 40nm, 50nm, 60nm and so on.

The light emitting layer 30 may be an organic light emitting layer or a quantum dot light emitting layer. When the light emitting layer 30 is an organic light emitting layer, the optoelectronic device 100 may be an organic electroluminescent device. When the light emitting layer 30 is a quantum dot light emitting layer, the optoelectronic device 100 may be a quantum dot electroluminescent device. The thickness of the light-emitting layer 30 can be, for example, 10 nm to 60 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm and so on.

Wherein, the material of the organic light-emitting layer is a material known in the art to use an organic light-emitting layer, for example, can be selected from but not limited to diaryl anthracene derivatives, distyryl aromatic derivatives, pyrene derivatives or fluorene derivatives, One or more of TBPe fluorescent material emitting blue light, TTPA fluorescent material emitting green light, TBRb fluorescent material emitting orange light, and DBP fluorescent material emitting red light.

Wherein, the material of the quantum dot light-emitting layer is quantum dots known in the art to be used in the quantum dot light-emitting layer, for example, one of red quantum dots, green quantum dots and blue quantum dots. The material of the quantum dot light-emitting layer is selected from at least one of single-structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials, and the single-structure quantum dots are selected from II-VI group compounds, IV-VI At least one of group III-V compound and I-III-VI group compound, the II-VI group compound is selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe 、CdSeS、CdSeTe、CdSTe、ZnSeS、ZnSeTe、ZnSTe、HgSeS、HgSeTe、HgSTe、CdZnS、CdZnSe、CdZnTe、CdHgS、CdHgSe、CdHgTe、HgZnS、HgZnSe、HgZnTe、CdZnSeS、CdZnSeTe、CdZnSTe、CdHgSeS、CdHgSeTe、CdHgSTe、HgZnSeS At least one of , HgZnSeTe and HgZnSTe, the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe , SnPbSeTe, SnPbSTe at least one, the III-V compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs , GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and at least one of InAlPSb, the I-III-VI group compound is selected from at least one of CuInS ₂ , CuInSe ₂ and AgInS ₂ ; the core of the quantum dot with the core-shell structure is selected from the above-mentioned single-structure quantum dot Any one of them, the shell material of the quantum dots with core-shell structure is selected from at least one of CdS, CdTe, CdSeTe, CdZnSe, CdZnS, CdSeS, ZnSe, ZnSeS and ZnS. It should be noted that, for the aforementioned single-component quantum dot material, or the core material of the core-shell structure quantum dot, or the shell material of the core-shell structure quantum dot, the chemical formula provided only shows the elemental composition, and does not show Indicate the content of each element, for example: CdZnSe only means that it is composed of three elements: Cd, Zn and Se. If it indicates the content of each element, it corresponds to Cd _x Zn _1-x Se, where 0<x<1. The particle size of the quantum dots may be, for example, 5 nm to 20 nm.

Please refer to FIG. 1 , in an embodiment, the optoelectronic device 100 may further include an electron transport layer 50 , and the electron transport layer 50 is located between the light emitting layer 30 and the cathode 40 . The material of the electron transport layer 50 may be a material known in the art for electron transport layers. For example, it may be selected from but not limited to one or more of inorganic nanocrystalline materials, doped inorganic nanocrystalline materials, and organic materials. Inorganic nanocrystalline materials may include: one or more of zinc oxide, titanium dioxide, tin dioxide, aluminum oxide, calcium oxide, silicon dioxide, gallium oxide, and zirconia, and doped inorganic nanocrystalline materials include zinc oxide doped One or more of dopant, titanium dioxide dopant, tin dioxide dopant, wherein, the doped inorganic nanocrystalline material is an inorganic material doped with other elements, and the doped element is selected from Mg, Ca, Li, Ga , Al, Co, Mn, etc., the doping ratio can be 0-50%; the organic material can include one or both of polymethyl methacrylate and polyvinyl butyral. The thickness may be, for example, 10 nm to 60 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, and the like.

It can be understood that, in addition to the above-mentioned functional layers, the optoelectronic device 100 can also add some functional layers that are conventionally used in optoelectronic devices to help improve the performance of optoelectronic devices, such as electron blocking layers, hole blocking layers, electron injection layers, hole Injection layer, interface modification layer, etc.

It can be understood that the material of each layer of the optoelectronic device 100 can be adjusted according to the light emission requirements of the optoelectronic device 100 .

It can be understood that the optoelectronic device 100 may be a positive optoelectronic device or an inverted optoelectronic device.

The embodiment of the present application also provides a display device, including the optoelectronic device provided in the present application. The display device can be any electronic product with display function. Electronic products include but are not limited to smart phones, tablet computers, laptops, digital cameras, digital video cameras, smart wearable devices, smart weighing electronic scales, car displays, TVs Or an e-book reader, wherein the smart wearable device may be, for example, a smart bracelet, a smart watch, a virtual reality (Virtual Reality, VR) helmet, and the like.

The embodiment of the present application also provides a method for preparing the optoelectronic device 100, including the step of preparing a hole transport film, using the preparation methods shown in step S10 and step S20 to prepare the hole transport film.

Please refer to FIG. 5, the embodiment of the present application provides a method for manufacturing a photoelectric device 100, including the following steps:

Step S31: providing the anode 20;

Step S32: preparing the hole transport film 10 on the anode 20 by the method for preparing the hole transport film 10;

Step S33 : sequentially forming a laminated light emitting layer 30 and a cathode 40 on the hole transport film 10 .

It can be understood that when the optoelectronic device 100 further includes the electron transport layer 50 , the step S33 is: sequentially forming the stacked electron transport layer 50 , the light emitting layer 30 and the cathode 40 on the hole transport film 10 .

Please refer to FIG. 6, the embodiment of the present application also provides another method for preparing a photoelectric device 100, which includes the following steps:

Step S41: providing a cathode 40, and forming a light-emitting layer 30 on the cathode 40;

Step S42: On the light-emitting layer 30, prepare the hole transport film 10 by the preparation method of the hole transport film 10;

Step S43 : forming the anode 20 on the hole transport film 10 .

It can be understood that, when the optoelectronic device 100 further includes the electron transport layer 50 , the step S41 is: providing the cathode 40 , and sequentially forming the laminated electron transport layer 50 and the light emitting layer 30 on the cathode 40 .

It should be noted that in this application, the anode 20, the hole transport film 10, the light emitting layer 30, the electron transport layer 50, the cathode 40 and other functional layers can be prepared by conventional techniques in the art, including but not limited to solution method and deposition Among them, solution methods include but are not limited to spin coating, coating, inkjet printing, blade coating, dipping, soaking, spraying, rolling or casting; deposition methods include chemical methods and physical methods, and chemical methods include but Not limited to chemical vapor deposition method, continuous ion layer adsorption and reaction method, anodic oxidation method, electrolytic deposition method or co-precipitation method, physical methods include but not limited to thermal evaporation coating method, electron beam evaporation coating method, magnetron sputtering method, multi-arc ion coating method, physical vapor deposition method, atomic layer deposition method or pulsed laser deposition method. When the anode 20 , the hole transport film 10 , the light emitting layer 30 , the electron transport layer 50 , the cathode 40 and other functional layers are prepared by the solution method, a drying process is required.

It can be understood that when the photoelectric device 100 further includes other functional layers such as an electron blocking layer, a hole blocking layer, an electron injection layer, a hole injection layer and/or an interface modification layer, the preparation method of the photoelectric device 100 also includes forming the Describe the steps of each functional layer.

It can be understood that the preparation method of the optoelectronic device 100 may also include an encapsulation step, the encapsulation material may be acrylic resin or epoxy resin, the encapsulation may be machine encapsulation or manual encapsulation, and the concentration of oxygen and water in the encapsulation step environment is low In order to ensure the stability of the optoelectronic device 100, it should be less than 0.1ppm.

Nickel oxide (NiOx) nanomaterials are known hole-transporting materials. The following will use nickel oxide nanomaterials as a comparative example of hole-transporting materials and specific examples of nickel oxide nanomaterials doped with triazine framework materials. The technical solutions and technical effects of the application are described in detail, and the following examples are only some examples of the application, and do not limit the application.

Example 1

This embodiment provides a quantum dot light-emitting diode and a preparation method thereof. With reference to FIG. The transport layer 50 and the cathode 40, wherein the hole transport film 10 is composed of nickel oxide nanomaterials including doped triazine framework materials.

The structure of each layer in the quantum dot light-emitting diode is as follows:

The material of the anode 20 is ITO, the thickness of the anode 20 is 55nm, and one side of the anode 20 is connected with a glass substrate.

The hole transport film 10 is made of nickel oxide nanomaterial doped with CTF-1, and the molar ratio of nickel oxide to CTF-1 is 1:1. The hole transport thin film 10 has a thickness of 60 nm. The structure of triazine framework material CTF-1 is shown in Figure 7. CTF-1 is a triazine framework material polymerized from 1, 3, 5-tricyanobenzene as a monomer, and its degree of polymerization is 1200.

The material of the light-emitting layer 30 is blue quantum dots with Cd _x Zn _1-x Se/ZnS core-shell structure, and the thickness is 40 nm.

The material of the electron transport layer 50 is zinc oxide nano material with a thickness of 40nm.

The material of the cathode 40 is aluminum with a thickness of 70nm.

The preparation method of quantum dot light-emitting diode in the present embodiment comprises the following steps:

Provide a glass substrate with an ITO anode 20, which is pretreated;

Provide nickel nitrate hexahydrate, CTF-1 and ethylene glycol, and mix to obtain a nickel nitrate mixture solution doped with CTF-1, wherein CTF-1 is obtained by polymerizing 1, 3, 5-tricyanobenzene as a monomer The triazine skeleton material, the molar ratio of nickel nitrate hexahydrate and CTF-1 is 1:1; dissolve sodium hydroxide in ethanol to form an alkaline solution; add the alkaline solution dropwise to nickel nitrate doped with CTF-1 In the mixture solution, adjust the pH=12, stir for 1 hour, and obtain a nickel oxide precursor doped with CTF-1; spin-coat the precursor solution on the anode 20, so that the precursor completely covers the anode 20, and heat it on a heating platform at 150°C After heat treatment for 60 min, a NiOx/CTF-1 composite hole transport film 10 with a thickness of 60 nm was obtained; wherein, the spin coating speed was 3000 rpm/min.

Spin-coat blue quantum dots with Cd _x Zn _1-x Se/ZnS core-shell structure on the hole transport layer 10 to obtain a light-emitting layer 30 with a thickness of 40 nm;

spin-coating a zinc oxide nanomaterial solution on the luminescent layer 30 to obtain an electron transport layer 50 with a thickness of 40 nm;

Evaporate a layer of metal aluminum on the electron transport layer 50 to obtain a cathode 40 with a thickness of 70nm;

Encapsulate to obtain a quantum dot light emitting diode.

Example 2

This embodiment provides a quantum dot light-emitting diode and a preparation method thereof. Compared with the quantum dot light-emitting diode of embodiment 1, the difference between the quantum dot light-emitting diode of this embodiment lies in: the material of the hole transport film 10 Differently, the material of the hole transport thin film 10 in this embodiment is nickel oxide nanomaterial doped with CTF-2, and the molar ratio of nickel oxide to CTF-2 is 1:1.2. The structure of the triazine framework material CTF-2 can be referred to in Figure 7. CTF-2 is a triazine framework material polymerized from p-cyanobenzene as a monomer, and the degree of polymerization is 1500.

Compared with the preparation method of the quantum dot light-emitting diode in Example 1, the difference in the preparation method of the quantum dot light-emitting diode in this embodiment is only that: in this embodiment, nickel chloride, CTF-2 and ethylene glycol are provided , mixed to obtain a nickel nitrate mixture solution doped with CTF-2, wherein CTF-2 is a triazine skeleton material formed by polymerizing p-cyanobenzene as a monomer, and the molar ratio of nickel chloride to CTF-2 is 1 : 1.2; Potassium hydroxide is dissolved in ethanol to form an alkaline solution; the alkaline solution is added dropwise to the nickel chloride mixture solution doped with CTF-2, adjusted to pH=10, and stirred for 1 hour to obtain doped CTF-2 Nickel oxide precursor; the precursor solution is spin-coated on the anode 20, so that the precursor completely covers the anode 20, heat treatment on a heating platform at 150°C for 90min, and a NiOx/CTF-2 composite hole transport film with a thickness of 60nm is obtained 10.

comparative example

This comparative example provides a quantum dot light-emitting diode and its preparation method. Compared with the quantum dot light-emitting diode of embodiment 1, the difference of the quantum dot light-emitting diode of this embodiment is only: the material of the hole transport film 10 different. The hole transport thin film 10 of this comparative example is made of nickel oxide nanomaterials, and the nickel oxide nanomaterials are not doped with triazine framework materials. In this comparative example, correspondingly no triazine framework material is mixed into the nickel oxide precursor solution.

The external quantum efficiency EQE and turn-on voltage of the optoelectronic device 100 of the above-mentioned examples 1-2 and the optoelectronic device of the comparative example were tested. Among them, the external quantum efficiency EQE and the turn-on voltage are measured by EQE optical testing equipment. Wherein, the turn-on voltage is the voltage when the brightness of the device is 1 nits. The test results are shown in Table 1 below.

Table I:

the	EQE(%)	Turn on voltage (V)
comparative example	4.5	3.53
Example 1	8.5	2.44
Example 2	7.3	2.41

It can be seen from Table 1 that, compared with the quantum dot light-emitting diodes in which the material of the hole transport film 10 is a nickel oxide nanomaterial in the comparative example, in Examples 1 and 2, the material of the hole transport film 10 is a metal doped with a triazine framework material. Quantum dot light-emitting diodes of oxide nanomaterials have higher luminous efficiency and lower turn-on voltage.

In Example 1 and Example 2, since the hole transport film 10 is doped with the added triazine framework material, a strong dipole is induced on the interface to increase the NiOx work function and reduce the hole injection barrier. It is beneficial to the electron-hole injection balance of the quantum dot light-emitting diode including the hole transport film 10, improves the luminous efficiency of the optoelectronic device 100, and improves the crystallinity and film-forming uniformity of nickel oxide, and optimizes the relationship with adjacent functions. layer or the light-emitting layer, so the conductivity is better, the carrier transport is more efficient, and the leakage current is smaller, which reduces the turn-on voltage.

A kind of hole-transporting thin film provided by the embodiment of the present application, its preparation method, and photoelectric device have been introduced in detail above. In this paper, specific examples have been used to illustrate the principle and implementation of the present application. The description of the above embodiment is only It is used to help understand the technical solution and its core idea of the present application; those skilled in the art should understand that it can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and These modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims (20)

1. A thin film, wherein the thin film comprises a metal oxide nanomaterial doped with a triazine framework material.
2. The thin film of claim 1, wherein the thin film is composed of metal oxide nanomaterials doped with a triazine framework material.
3. The film according to claim 1, wherein the triazine skeleton material is polymerized from monomers, and the monomers are nitrile compounds containing aromatic groups.
4. The film according to claim 3, wherein the aromatic group-containing nitrile compound is selected from the group consisting of cyano-substituted benzene ring compounds, cyano-substituted pyridine compounds, cyano-substituted pyrimidine compounds, and cyano-substituted biphenyl compounds , one or more of cyano-substituted naphthalene ring compounds.
5. The film according to claim 3, wherein the aromatic group-containing nitrile compound comprises at least two cyano groups, and the aromatic group-containing nitrile compound is selected from tricyanobenzene, p-cyanobenzene, biphenyl dinitrile , one or more of pyridinedicarbonitrile.
6. The film according to claim 2, wherein, in the metal oxide nanomaterial doped with a triazine framework material, the molar ratio of the metal oxide to the triazine framework material is in the range of 1:(1-1.5) .
7. The film according to claim 1, wherein the metal oxide nanomaterial is selected from one or more of nickel oxide, molybdenum oxide, tungsten oxide, copper oxide, vanadium oxide and chromium oxide Various.
8. The film according to claim 1, wherein the degree of polymerization of the triazine framework material is 900-3000.
9. A method for preparing a thin film, comprising the steps of:

   Preparation of metal oxide precursors doped with triazine framework materials;

   A substrate is provided, and the metal oxide precursor doped with a triazine framework material is arranged on the substrate to obtain a thin film comprising a metal oxide nanomaterial doped with a triazine framework material.
10. The preparation method according to claim 9, wherein the step of preparing a metal oxide precursor doped with a triazine framework material comprises:

    Provide metal salt, triazine framework material and solvent, mix, obtain the metal salt mixture solution doped with triazine framework material;

    The base is added into the metal salt mixture solution to obtain the metal oxide precursor doped with the triazine framework material.
11. The preparation method according to claim 10, wherein the metal salt is selected from one or more of metal chloride salts, metal nitrates, and metal acetylacetonate salts.
12. The preparation method according to claim 10, wherein the alkali is selected from one or more of sodium hydroxide, potassium hydroxide and tetramethylammonium hydroxide.
13. The preparation method according to claim 10, wherein the solvent is selected from one or more of methanol, ethanol, ethylene glycol, glycerol, butanol, DMF, and DMSO.
14. The preparation method according to claim 9, wherein, the substrate is provided, and the metal oxide precursor of the doped triazine framework material is arranged on the substrate to obtain a metal oxide nanometer comprising a doped triazine framework material. The steps of thin film of material include:

    providing a substrate, and disposing the metal oxide precursor doped with a triazine framework material on the substrate by a solution method;

    drying treatment to obtain the thin film of the metal oxide nanomaterial including the doped triazine framework material.
15. A photoelectric device, comprising a stacked anode, a hole transport layer, a light-emitting layer and a cathode, wherein: the hole transport layer is the thin film according to any one of claims 1-8, or, the hole transport layer The layer is produced by the method for producing a film according to any one of claims 9-14.
16. The optoelectronic device according to claim 15, wherein,

    The light-emitting layer is an organic light-emitting layer or a quantum dot light-emitting layer, and the material of the organic light-emitting layer is selected from diaryl anthracene derivatives, stilbene aromatic derivatives, pyrene derivatives or fluorene derivatives, TBPe fluorescent materials, One or more of TTPA fluorescent materials, TBRb fluorescent materials and DBP fluorescent materials; the material of the quantum dot light-emitting layer is selected from at least one of single-structure quantum dots, core-shell quantum dots and perovskite semiconductor materials species, the single-structure quantum dots are selected from at least one of II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds, and the II-VI group compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, At least one of HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, At least one of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, the III-V group compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, At least one of GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb, the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2; The core of the quantum dot of the core-shell structure is selected from any one of the above-mentioned single-structure quantum dots, and the shell material of the quantum dot of the core-shell structure is selected from CdS, CdTe, CdSeTe, CdZnSe, CdZnS, CdSeS, ZnSe, At least one of ZnSeS and ZnS.
17. The optoelectronic device according to claim 15, wherein the anode and the cathode are each independently selected from one or more of metal electrodes, carbon material electrodes, metal oxide electrodes and composite electrodes, and the metal electrodes are selected from From one or more of Al, Ag, Cu, Mo, Au, Ba, Ca and Mg, the carbon material electrode is selected from one or more of graphite, carbon nanotubes, graphene and carbon fibers; The metal oxide electrode is selected from one or more of doped or non-doped ITO, FTO, ATO, AZO, GZO, IZO, MZO and AMO, and the composite electrode is selected from AZO/Ag/AZO, AZO/ Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS, One or more of ZnS/Al/ZnS, TiO ₂ /Ag/TiO ₂ and TiO ₂ /Al/TiO ₂ .
18. The optoelectronic device according to claim 15, wherein the optoelectronic device further comprises an electron transport layer located between the light emitting layer and the cathode.
19. The optoelectronic device according to claim 15, wherein the material of the electron transport layer can be selected from one or more of inorganic nanocrystalline materials, doped inorganic nanocrystalline materials, and organic materials, and the inorganic nanocrystalline materials One or more selected from zinc oxide, titanium dioxide, tin dioxide, aluminum oxide, calcium oxide, silicon dioxide, gallium oxide, and zirconium oxide, and the doped inorganic nanocrystalline material includes zinc oxide dopant, titanium dioxide One or more of dopant, tin dioxide dopant, wherein, the doping element contained in the doped inorganic nanocrystalline material is selected from Mg, Ca, Li, Ga, Al, Co, Mn, The organic material is selected from one or both of polymethyl methacrylate and polyvinyl butyral.
20. The photovoltaic device according to claim 15, wherein the hole transport layer has a thickness of 10 to 60 nm.

Images